FRIDAY, Aug. 22, 2014 (HealthDay News) -- People who use reduced-nicotine cigarettes don't smoke more to make up for the lower levels of nicotine, according to a new study.

This means they don't inhale more toxic chemicals than other smokers, the researchers say.

The month-long study included 72 adult smokers, aged 18 to 65, who smoked regular cigarettes with nicotine emission levels of 1.2 milligrams (mg) each for one week. The participants then switched to reduced-nicotine cigarettes for the next three weeks.

In each of those three weeks, the participants smoked cigarettes with decreasing nicotine emission levels -- 0.6 mg, 0.3 mg, and 0.05 mg or less.

At the end of each week, urine and breath samples were collected from the smokers. The number of cigarettes smoked, and the number of puffs taken from cigarettes by the participants did not change during the study. The findings are published Aug. 22 in the journal Cancer Epidemiology, Biomarkers & Prevention.

Also, there were no changes in the levels of carbon monoxide in their breath and no difference in urine levels of 1-hydroxypyrene, a potentially cancer-causing chemical in cigarettes.

"As a result of the 2009 Tobacco Act, the U.S. Food and Drug Administration has the mandate to reduce nicotine levels in cigarettes to negligible amounts," said study author David Hammond, associate professor in the School of Public Health and Health Systems at the University of Waterloo in Ontario, Canada.

However, concerns have arisen that smokers will be exposed to greater amounts of toxic chemicals in smoke as they try to extract more nicotine from cigarettes, he explained. "The current study suggests that this may not be the case," he said in a journal news release.

Instead, the findings show "that smokers are unable or unwilling to compensate when there is markedly less nicotine in the cigarette and when the experience of smoking is far less rewarding," said Hammond. "Our study may help regulators anticipate the possible consequences of mandatory nicotine reductions in cigarettes."

Sources of funding for the study included Health Canada and the Canadian Cancer Society. No cigarette makers were involved.